what is a pulp vitality test

The pulp is the soft core of a tooth: nerves, blood vessels and connective tissue running from the crown down to the root tip. Whether that pulp is healthy, irritated, badly inflamed or dead decides most of what happens next. A filling may be enough, or you may need root canal treatment, or the tooth may need nothing at all. Pulp tests are how your dentist finds out.

Strictly speaking, they test sensation

Here is a detail most patients are never told. The common tests check whether the nerve responds, not whether blood is flowing. A true "vitality" test would measure blood supply directly, and the tools for that, such as pulse oximetry or laser Doppler probes adapted for teeth, are mostly used in research and specialist settings. In everyday dentistry, "vitality testing" means sensibility testing, and dentists interpret it with that limit in mind.

The main tests

• Cold test: a cotton pellet chilled with refrigerant spray, or ice, is placed on the dried tooth. It is quick, cheap and the most widely used.
• Heat test: warmed gutta-percha or a heated instrument. Used less often, mainly when your complaint is pain with hot food or drink.
• Electric pulp test (EPT): a small probe with a dab of toothpaste sends a gradually rising, very weak current. You feel a tingle or warmth and raise your hand. It shows whether the nerve responds at all, not how inflamed it is.
• Test cavity: rarely, a dentist drills a tiny hole without numbing to see if the tooth feels it. This is a last resort.

Reading the result

Your dentist tests a healthy neighbour first so you both know what normal feels like. Then the suspect tooth. What matters is the difference:

• A response similar to the neighbour, fading quickly, usually means a healthy pulp.
• An exaggerated but short response suggests reversible pulpitis: irritated, but likely to settle once the cause is treated.
• Pain that lingers for many seconds or minutes after the stimulus is removed suggests irreversible pulpitis.
• No response may mean the pulp has died, which is then checked against the X-ray and tapping test.

When the test can mislead

• False "dead" readings: teeth with large fillings or crowns, older teeth whose pulp has shrunk, and teeth recently injured. After a two-wheeler fall or a blow, a front tooth may not respond for weeks and then recover, which is why your dentist often waits and retests rather than starting a root canal straight away.
• False "alive" readings: very anxious patients sometimes raise a hand in anticipation, and a tooth with several canals may have one part alive and another dead.
• Young teeth: teeth whose roots are still forming in children respond unreliably to EPT.
• Pacemakers: mention one if you have it. Most modern devices are not affected, but your dentist will choose the test with that in mind.

What happens next

The vitality result is one piece of the picture, combined with your symptoms, a tapping test and an X-ray. If the pulp looks healthy or only irritated, the aim is to save it with a filling. If it looks irreversibly inflamed or dead, root canal treatment or, sometimes, extraction is discussed. Difficult or doubtful teeth may be referred to our endodontics department. Our root canal questions and the diagnosis hub have more on what each result leads to.